A thermistor bolometer has been used to determine the radiant energy transfer from a typical laboratory plasma. Radiation has been found to be a significant mechanism of energy transfer from an atmospheric argon plasma jet, amounting to as much as 18 percent of the net power input to the plasma. The radiant energy transfer from an atmospheric nitrogen plasma jet under comparable conditions has been found to be less than 1 percent of the net power input to the plasma. The radiative power density...

Topics: DTIC Archive, Berry, James M, NORTHWESTERN UNIV EVANSTON IL GAS DYNAMICS LAB, *PLASMA JETS, ARGON,...

This report describes several types of parameterizations commonly used in cloud and fog models to calculate the effects of radiant energy exchange in both the infrared and solar portions of the spectrum. The types of parameterizations used in several models of radiation fog have been summarized in the main text and detailed in the appendix, along with a few summaries of supporting studies. In general, the treatment of radiant exchange includes spectral resolution at the level of band models,...

Topics: DTIC Archive, Davis, John M, BATTELLE COLUMBUS LABS RESEARCH TRIANGLE PARK NC, *ENERGY TRANSFER,...

A radiant heat flux gage calibration system exists in the Flight Loads Laboratory at NASA's Dryden Flight Research Center. This calibration system must be well understood if the heat flux gages calibrated in it are to provide useful data during radiant heating ground tests or flight tests of high speed aerospace vehicles. A part of the calibration system characterization process is to develop a numerical model of the flat plate heater element and heat flux gage, which will help identify errors...

Topics: NASA Technical Reports Server (NTRS), RADIANT HEATING, HEAT FLUX, CALIBRATING, NUMERICAL ANALYSIS,...

A full 3-D Analysis of super-radiant (bunched electron) free electron harmonic radiation is presented. A generalized form of the FEL pendulum equation was derived and numerically solved. Both spectral and phasor formulation were developed to treat the radiation in the time domain. In space the radiation field is expanded in terms of either a set of free space discrete modes or plane waves. The numerical solutions reveal some new distinctly 3-D effects to which we provide a physical explanation.

Topics: DTIC Archive, Gover, A., BROOKHAVEN NATIONAL LAB UPTON NY NATIONAL SYNCHROTRON LIGHT SOURCE, *FREE...

The manner in which large hydrogen bubbles rise, mix, burn, and radiate is predicted for bubbles of varying diameter, initial velocity, and crosswind velocity using simplified models. The motion of buoyant gas bubbles in general is shown to be accurately described by the simplified entrainment model of Shui and Weyl for a variety of bubble sizes and compositions including small hydrogen bubbles as reported in the Russian literature, large bubbles resulting from the combustion of stoichiometric...

Topics: DTIC Archive, Petersen,Priscilla C, AERONAUTICAL RESEARCH ASSOCIATES OF PRINCETON INC N J,...

The development of an analytical-numerical model to predict radiant emission or absorption is discussed. A voigt profile is assumed to predict the spectral qualities of a singlet atomic transition line for atomic species of interest to the OPAD program. The present state of this model is described in each progress report required under contract. Model and code development is guided by experimental data where available. When completed, the model will be used to provide estimates of specie...

Topics: NASA Technical Reports Server (NTRS), ABSORPTION SPECTRA, EMISSION SPECTRA, ENGINE MONITORING...

A non-flowing, electrically heated test rig was developed to verify computer codes that calculate radiant energy propagation from nozzle geometries that represent aircraft propulsion nozzle systems. Since there are a variety of analysis tools used to evaluate thermal radiation propagation from partially enclosed nozzle surfaces, an experimental benchmark test case was developed for code comparison. This paper briefly describes the nozzle test rig and the developed analytical nozzle geometry...

Topics: NASA Technical Reports Server (NTRS), AIRCRAFT ENGINES, COMPUTER PROGRAMS, EXHAUST NOZZLES, JET...

Briefing charts only.

Topics: DTIC Archive, Dimpfl, William L, SPECTRAL SCIENCES INC BURLINGTON MA, *EARTH ORBITS, MATHEMATICAL...

Geometric shape factors were computed and applied to satellite simulated irradiance measurements to estimate Earth emitted flux densities for global and zonal scales and for areas smaller than the detector field of view (FOV). Wide field of view flat plate detectors were emphasized, but spherical detectors were also studied. The radiation field was modeled after data from the Nimbus 2 and 3 satellites. At a satellite altitude of 600 km, zonal estimates were in error 1.0 to 1.2 percent and...

Topics: NASA Technical Reports Server (NTRS), EARTH SURFACE, RADIANT FLUX DENSITY, RADIATION MEASUREMENT,...

Past missions have shown that the earth's albedo can have a significant effect on the sun sensors used for spacecraft attitude control information. In response to this concern, an algorithm was developed to simulate this phenomenon, consisting of two parts, the physical model of albedo and its effect on the sun sensors. This paper contains the theoretical development of this model, practical operational notes, and its implementation in a FORTRAN subroutine.

Topics: NASA Technical Reports Server (NTRS), ATTITUDE CONTROL, DIFFUSE RADIATION, EARTH ALBEDO,...

A general method for extracting particle size dependent information from experimental rate/formulation data was developed from the statistical methodology. This technique was employed to correlate the data bases of Miller. Results showed that, by employing an interaction parameter of 4, both additive and additive free data could be correlated to standard error of estimate below 10.5%. The effect of steady radiant energy deposition on steady and nonsteady burning was explored. Results showed...

Topics: DTIC Archive, Glick,R L, THIOKOL CORP HUNTSVILLE ALA HUNTSVILLE DIV, *COMBUSTION, *SOLID ROCKET...

A computational model has been developed and applied for calculating radiant heat flux from an electric arc using real gas properties and taking into account both self absorption and space varying temperature. The model requires knowledge of the temperature profile as an input. Temperature profiles were measured spectrographically using an air arc at one and 2.4 atmospheres. These measured profiles plus some simple analytic ones which satisfied boundary conditions were used to calculate radiant...

Topics: DTIC Archive, Marston, C H, GENERAL ELECTRIC CO PHILADELPHIA PA MISSILE AND SPACE DIV, *ELECTRIC...

A theoretical analysis is presented to study the extinction characteristics of a diffusion flame near the leading edge of a thin fuel plate in slow, forced convective flows in a microgravity environment. The mathematical model includes two-dimensional Navier-Stokes momentum, energy and species equations with one-step overall chemical reaction using second-order finite rate Arrhenius kinetics. Radiant heat loss on the fuel plate is applied in the model as it is the dominant mechanism for flame...

Topics: NASA Technical Reports Server (NTRS), CONVECTIVE FLOW, DIFFUSION FLAMES, EXTINGUISHING,...

The current effort addresses two issues important to the research conducted by the Thermal Radiation Group at Virginia Tech. The first research topic involves the development of a method which can properly model the diffraction of radiation as it enters an instrument aperture. The second topic involves the study of a potential next-generation space-borne radiometric instrument concept. Presented are multiple modeling efforts to describe the diffraction of monochromatic radiant energy passing...

Topics: NASA Technical Reports Server (NTRS), EARTH RADIATION BUDGET, MATHEMATICAL MODELS, RADIANT FLUX...

Two different Michelson interferometer measurement systems were used to collect spectral radiant intensity data describing blackbody emissions. These data were subjected to statistical and numerical analysis for the purpose of characterizing infrared measurement variability. A mathematical model has been postulated to describe the variability of infrared measurements based on the results of this analysis. Recommendations are made for future study to verify and extend the results presented in...

Topics: DTIC Archive, Matthis,N K, ARINC RESEARCH CORP ANNAPOLIS MD, *INFRARED SIGNATURES, *ANALYSIS OF...

An investigation of a simple self-similar flow model for an external nuclear pulse propulsion system indicates that to achieve the high effective specific impulse of such a system three principal factors are required. The are (1) attaining pulses of optimum energy, (2) attaining good propellant collimation, and (3) using an ablative material for the pusher surface which has high absorptivity for radiant energy at the propellant stagnation temperature.

Topics: NASA Technical Reports Server (NTRS), NUCLEAR PROPULSION, PROPULSION SYSTEM PERFORMANCE, SPECIFIC...

The report describes a method for calculating safe separation distances from a nuclear fireball from the standpoint of permanent injury (chorioretinal burns) and temporary effects (flashblindness). Weapon characteristics, atmospheric transmission, and the interaction of radiant energy with the eye are discussed. Predicted safe separation distances from a nuclear flash for humans are presented as functions of observer altitude, height of burst, weapon yield, and day or night conditions.

Topics: DTIC Archive, Allen, R G, SCHOOL OF AEROSPACE MEDICINE BROOKS AFB TX, *FLASHBLINDNESS, *NUCLEAR...

Experimental and analytical investigations focusing on secondary atomization and ignition characteristics of aluminum/liquid hydrocarbon slurry propellants were conducted. Experimental efforts included the application of a laser-based, two-color, forward-scatter technique to simultaneously measure free-flying slurry droplet diameters and velocities for droplet diameters in the range of 10-200 microns. A multi-diffusion flame burner was used to create a high-temperature environment into which a...

Topics: NASA Technical Reports Server (NTRS), ALUMINUM, IGNITION, LIQUID ATOMIZATION, METAL COMBUSTION,...

The objectives of this study were to model the surface heating of asphaltic concrete pavements and to investigate the thermal properties (conductivity, specific heat, and diffusivity) of asphaltic concrete. The thermal properties of six laboratory prepared asphaltic concrete mixes at three asphalt contents were determined. As a result of testing four or five replicate samples of each of the eighteen mix combinations, it was concluded that average values of specific heat and diffusivity,...

Topics: DTIC Archive, Highter,W H, TENNESSEE UNIV KNOXVILLE DEPT OF CIVIL ENGINEERING, *Asphalt, *Heating,...

A one-dimensional analytical model for the steady state combustion of a multiparticle cloud of boron in air was established. This model stressed the importance of radiant heat transfer from the luminous flame and heat of combustion from burning particles adhering to the combustor walls to heat the suspended particles to ignition temperature. A steady state, self-sustained flame of elemental boron in air was investigated to verify the model. Trona amorphous boron powder, with nominal particle...

Topics: DTIC Archive, Ormand, Lowell W., AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF...

This paper presents a radiative transfer model that has been developed to accurately predict the atmospheric radiant flux in both the infrared and the solar spectrum with a minimum of computational effort. The model is designed to be included in numerical climate models To assess the accuracy of the model, the results are compared to other more detailed models for several standard cases in the solar and thermal spectrum. As the thermal spectrum has been treated in other publications, we focus...

Topics: NASA Technical Reports Server (NTRS), MATHEMATICAL MODELS, RADIATIVE TRANSFER, CLIMATE MODELS,...

This paper presents a radiative transfer model that has been developed to accurately predict the atmospheric radiant flux in both the infrared and the solar spectrum with a minimum of computational effort. The model is designed to be included in numerical climate models. To assess the accuracy of the model, the results are compared to other more detailed models for several standard cases in the solar and thermal spectrum. As the thermal spectrum has been treated in other publications we focus...

Topics: NASA Technical Reports Server (NTRS), MATHEMATICAL MODELS, RADIATIVE TRANSFER, SOLAR SPECTRA,...

A solid rocket booster (SRB) thermal radiation model, capable of defining the influence of the plume flowfield structure on the magnitude and distribution of thermal radiation leaving the plume, was prepared and documented. Radiant heating rates may be calculated for a single SRB plume or for the dual SRB plumes astride the space shuttle. The plumes may be gimbaled in the yaw and pitch planes. Space shuttle surface geometries are simulated with combinations of quadric surfaces. The effect of...

Topics: NASA Technical Reports Server (NTRS), BOOSTER ROCKET ENGINES, MATHEMATICAL MODELS, SOLID PROPELLANT...

The microwave characteristics of calm, rough, and foam-covered ocean surfaces were studied, and a technique was developed for deriving thermodynamic ocean surface temperatures from brightness temperatures measured by an earth-orbiting radiometer. This investigation encompassed frequencies in the range 1 to 10 GHz (wavelength range of 30 to 3 cm) and was based on the use of a one-dimensional geometrical optics roughness model, including shadowing and multiple scattering of radiant...

Topics: NASA Technical Reports Server (NTRS), BRIGHTNESS TEMPERATURE, MICROWAVES, OCEAN SURFACE, EARTH...

This paper presents a radiative transfer model that has been developed to accurately predict the atmospheric radiant flux in both the infrared and the solar spectrum with a minimum of computational effort. The model is designed to be included in numerical climate models. To assess the accuracy of the model, the results are compared to other more detailed models for several standard cases in the solar and thermal spectrum. As the thermal spectrum has been treated in other publications, we focus...

Topics: NASA Technical Reports Server (NTRS), RADIATIVE TRANSFER, MATHEMATICAL MODELS, CLIMATE MODELS,...

This report covers the radiant intensity of the infrared sky background and the amplitude of the sky gradient. Measurement of the infrared sky background has been a more or less continuous program since July 1953 and a continuous record of the work accomplished can be gleaned from the reports issued, which are included in the reference lists. Both the radiometric data and the gradient data are discussed. The actual data have been presented in Reports No. 1, 2, and 3 preceding this final report...

Topics: DTIC Archive, Eisele, R E, THOMPSON RAMO WOOLDRIDGE INC LOS ANGELES CA, *INFRARED RADIATION,...

Heat pipes have been considered for use on wing leading edge for over 20 years. Early concepts envisioned metal heat pipes cooling a metallic leading edge. Several superalloy/sodium heat pipes were fabricated and successfully tested for wing leading edge cooling. Results of radiant heat and aerothermal testing indicate the feasibility of using heat pipes to cool the stagnation region of shuttle-type space transportation systems. The test model withstood a total seven radiant heating tests,...

Topics: NASA Technical Reports Server (NTRS), AEROSPACE VEHICLES, AEROTHERMODYNAMICS, COMPOSITE MATERIALS,...

A drop tube-Impulse Atomization technique was used to produce copper droplets. In this method, energy is transferred to a liquid by plunger movement resulting in spherical droplets emanating from orifices. A mathematical model of the evolution of droplet velocity and temperature at various heights for different sized droplets was developed. A two-color pyrometer, DPV-2000, and a shadowgraph were used to measure droplets radiant energy, diameter and velocity. The temperature values from the...

Topics: NASA Technical Reports Server (NTRS), ATOMIZING, COPPER, DROPS (LIQUIDS), MATHEMATICAL MODELS, REAL...

A thermal IR exitance model of a plant canopy based on a mathematical abstraction of three horizontal layers of vegetation was developed. Canopy geometry within each layer is quantitatively described by the foliage and branch orientation distributions and number density. Given this geometric information for each layer and the driving meteorological variables, a system of energy budget equations was determined and solved for average layer temperatures. These estimated layer temperatures,...

Topics: DTIC Archive, Kimes, D S, NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GREENBELT MD GODDARD SPACE...

A mathematical model of a pyrotechnic flame has been developed and validated. The model utilizes a computer program to calculate the relative radiant power of flares containing any of the alkali metals. The computation takes into consideration known system variables such as formulation, candle size, displacement along the plume axis, and atmospheric pressure. These effects were evaluated over a wide range of conditions and the computed spectra follow the established experimental spectra trends....

Topics: DTIC Archive, Dillehay, D. R., LONGHORN ARMY AMMUNITION PLANT MARSHALL TX, *PYROTECHNICS, *LINE...

Starting from the general measurement equation, it is shown that a NFOV scanner can be approximated by a spatially invariant system whose point spread function depends on the detector shape and angular characteristics and electrical filter transfer function for given patches at the top of the atmosphere. The radiometer is modeled by a detector, electrical filter, analog to digital converter followed by a reconstruction filter. The errors introduced by aliasing and blurring into a reconstruction...

Topics: NASA Technical Reports Server (NTRS), EARTH RADIATION BUDGET EXPERIMENT, ERROR ANALYSIS, FIELD OF...

The Hg/Cd/Te solidification in a Bridgman cell was thermally analyzed by Continuum's VAST code. The energy equation is solved in an axisymmetric, quasi steady domain for both the molten and solid alloy regions. Alloys composition is calculated by a simplified one dimensional model to estimate its effect on melt thermal conductivity and, consequently, on the temperature field within the cell. Solidification is assumed to occur at a fixed temperature of 979 K. Simplified boundary conditions are...

Topics: NASA Technical Reports Server (NTRS), BRIDGMAN METHOD, CRYSTAL GROWTH, THERMAL ANALYSIS, THERMAL...

A model has been developed that describes the thermal interaction of an externally applied radiant energy flux with the combustion zone of a burning homogeneous solid propellant. It is shown that only the radiation reaching the propellant surface, and absorbed within the solid phase, can effectively induce burning rate augmentation. Many conditions have been investigated in detail, including the limiting cases of solid-phase surface absorption and deep in-depth absorption with heat generation....

Topics: DTIC Archive, Ibiricu, M M, Aungst, W P, Williams, F A, ARMY BALLISTIC RESEARCH LAB ABERDEEN...

A new technique for the study of processes related to propellant combustion instability has been employed in which burning rate variations produced by a periodic radiant heat flux are measured. The phase angle between the perturbing flux and the burning rate response and the dependence of the magnitude of the response on the driving frequency are obtained. As the frequency of the perturbing flux increases, magnitude of the reaction is observed to first increase and then to pass through a...

Topics: DTIC Archive, Mihlfeith, C Max, UTAH UNIV SALT LAKE CITY DEPT OF CHEMICAL ENGINEERING, *SOLID...

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The Thermal Radiation Group, a laboratory in the department of Mechanical Engineering at Virginia Polytechnic Institute and State University, is currently working towards the development of a new technology for cavity-based radiometers. The radiometer consists of a 256-element linear-array thermopile detector mounted on the wall of a mirrored wedgeshaped cavity. The objective of this research is to provide analytical and experimental characterization of the proposed radiometer. A dynamic...

Topics: LASER PROPULSION, UNSTRUCTURED GRIDS (MATHEMATICS), RAY TRACING, PLASMA RADIATION, SPARK IGNITION,...

A multi-level model, based on the primitive equations, is developed for simulating the temperature and velocity fields produced in the world ocean by differential heating and surface wind stress. The model ocean has constant depth, free slip at the lower boundary, and neglects momentum advection; so that there is no energy exchange between the barotropic and baroclinic components of the motion, although the former influences the latter through temperature advection. The ocean model was designed...

Topics: NASA Technical Reports Server (NTRS), HYDROGRAPHY, OCEAN CURRENTS, OCEAN MODELS, SOLAR RADIATION,...

This report documents the efforts of nearly all of the active optical modelers of the world to establish a standard set of optical input parameters and of radiant flux outputs to be expected in a hydrosol that exhibits these optical parameters. I contributed output from the NRL optical model (Monte Carlo) for comparisons of output for molecular water, a standard hydrosol scattering function, and the contribution of water Raman scattering. Optical energy trapping near the water/air interface was...

Topics: DTIC Archive, Stavn, Robert H, NORTH CAROLINA UNIV AT GREENSBORO DEPT OF BIOLOGY, *MATHEMATICAL...

The program had the objective of developing a computer routine to determine the initiation and spread of fire in high density high-rise areas following a nuclear detonation, and its effects on the street environment. The result of this endeavor is a computer code that evaluates the probable number and floor locations of fires, the rate of heat generation from built-up areas, the radiant intensities in the streets, and the induced winds as functions of time. Provisions were made to keep the code...

Topics: DTIC Archive, Takata, A N, IIT RESEARCH INST CHICAGO IL, *NUCLEAR EXPLOSIONS, *URBAN AREAS, *FIRES,...

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The Clouds and the Earth's Radiant Energy System (CERES) is a program sponsored by the National Aeronautics and Space Administration (NASA) aimed at evaluating the global energy balance. Current scanning radiometers used for CERES consist of thin-film thermistor bolometers viewing the Earth through a Cassegrain telescope. The Thermal Radiation Group, a laboratory in the Department of Mechanical Engineering at Virginia Polytechnic Institute and State University, is currently studying a new...

Topics: COMPUTATIONAL GRIDS, COMPUTER PROGRAMMING, APPLICATIONS PROGRAMS (COMPUTERS), SOFTWARE ENGINEERING,...

As part of a technology program to investigate the transient heating problems associated with high-speed carriage of conventional stores, an analytical and experimental thermal analysis was conducted on a guided bomb. The objective of this work was to investigate the technology necessary to develop an analytic model from which store internal component thermal response could be generated. In addition, a radiant-heat ground test was conducted on instrumented flight hardware for the purpose of...

Topics: DTIC Archive, Crain, W K, ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFB TN, *GUIDED BOMBS,...

This report describes the status of the development of a method for predicting the heat release rate of wood for different thicknesses, moisture contents, and exposure conditions. A computer program has been set up on a microcomputer. Experimental techniques have been devised to obtain the input data required by the model. These include (1) the thermal conductivity as a function of temperature and percent loss, (2) the kinetic constants needed to describe the mass loss rate, (3) the heat of...

Topics: DTIC Archive, Parker,W J, NATIONAL BUREAU OF STANDARDS WASHINGTON DC CENTER FOR FIRE RESEARCH,...

This element-contribution model is programmed so that the distribution of infrared radiation from a ship target can be calculated for any aspect and any infrared waveband. The present application is to simulate the images formed by the guidance system of an imaging infrared antiship missile. The input data needed are the surface temperatures and emissivities and shapes of the main structures and the equivalent black body temperatures of the sky and sea surface. The shape of each ship is...

Topics: DTIC Archive, Scott, O S, ELECTRONICS RESEARCH LAB SALISBURY (AUSTRALIA), *INFRARED IMAGES,...

The GOES Product Generation System (GPGS) is a set of computer codes and scripts that enable the assimilation of real-time Geostationary Operational Environmental Satellite (GOES) data into regional-weather-forecasting mathematical models. The GPGS can be used to derive such geophysical parameters as land surface temperature, the amount of precipitable water, the degree of cloud cover, the surface albedo, and the amount of insolation from satellite measurements of radiant energy emitted by the...

Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, GEOSYNCHRONOUS ORBITS, RADIANT FLUX...

Insolation radiometers (normal incidence pyrheliometers) are used to measure the solar radiation incident on solar concentrators for calibrating thermal power generation measurements. The measured insolation value is dependent on the atmospheric transparency, solar elevation angle, circumsolar radiation, and radiometer field of view. The radiant energy entering the thermal receiver is dependent on the same factors. The insolation value and the receiver input will be proportional if the...

Topics: NASA Technical Reports Server (NTRS), INSOLATION, PARABOLIC REFLECTORS, RADIOMETERS, RAY TRACING,...

In the late 1950s, the earliest models describing the thermal response of ablative materials were based on the heat of ablation concept, which is an empirical approach that was reasonable for the types of materials of interest at that time. In the early-mid 60s the models were expanded to include pyrolysis since organic resin composites became the TPS materials of interest. However, surface recession was still predominantly modeled via empirical correlation. The development of the 1-D CMA...

Topics: NASA Technical Reports Server (NTRS), ABLATION, ABLATIVE MATERIALS, TEMPERATURE EFFECTS,...

Natural and forced ventilation tests were conducted during 1964 at eight shelter sites. Included were: three (summer) tests in high-rise building core areas; two (summer) tests in public school corridors and basements; one (summer) test in a home basement; one (summer) test in a buried community shelter; one (winter) test in a buried private shelter. Using electro- mechanical 'Simocs' to simulate shelter occupancy, the resulting physical environment was measured and analyzed. Manual ventilation...

Topics: DTIC Archive, PANERO (GUY B) INC NEW YORK, *VENTILATION, *FALLOUT SHELTERS, HEAT TRANSFER,...

The influence of polarization filtering on maximum detection, recognition, and identification ranges of a generic second generation FLIR sensor is examined with a computational model. The scenario studied represents a second generation FLIR sensor mounted on an aircraft in level flight at 3OOm approaching a ship target. The target ship radiant signature is modeled with an advanced infrared signature prediction program, MuSES (Multi-Service Electro-Optic Signature) . A weather file...

Topics: DTIC Archive, Yildirim, Mehmet, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *POLARIZATION, *FORWARD...

Localized ignition is initiated by an external radiant source at the middle of a thermally thin sample under external slow flow, simulating fire initiation in a spacecraft with a slow ventilation flow. Two ignition configurations are simulated, one across the sample surface creating a line shaped flame front (two-dimensional, 2-D, configuration) and the other a small circular ignition (three-dimensional, 3-D, configuration). Ignition, subsequent transition to simultaneously upstream and...

Topics: NASA Technical Reports Server (NTRS), FLAME PROPAGATION, IGNITION, MICROGRAVITY, COMPUTERIZED...

This report summarizes models for the high energy pulsed arc discharge used for high energy laser pumping. Homogeneous temperature models are discussed in which the radiant emission is balanced by the electrical power input. These models have been evaluated at various energy levels for the temperature which has been measured within the arc (assuming local thermal equilibrium). The models included the continuum spectral absorptivity calculated according to Biberman + Norman (using the Zeta...

Topics: DTIC Archive, Church, Charles H, WESTINGHOUSE RESEARCH LABS PITTSBURGH PA, *ELECTRIC DISCHARGES,...

The impact of Asian dust on cloud radiative forcing during 2003-2006 is studied by using the Earth's Radiant Energy Budget Scanner (CERES) data and the Fu-Liou radiative transfer model. Analysis of satellite data shows that the dust aerosol significantly reduced the cloud cooling effect at TOA. In dust contaminated cloudy regions, the 4-year mean values of the instantaneous shortwave, longwave and net cloud radiative forcing are -138.9, 69.1, and -69.7 Wm(sup -2), which are 57.0, 74.2, and...

Topics: NASA Technical Reports Server (NTRS), AEROSOLS, ASIA, CLOUD PHYSICS, DUST, RADIATIVE TRANSFER,...